Using a home blood pressure monitor

We explain how to take blood pressure at home and what the readings mean. If you’ve been diagnosed with high blood pressure, home monitoring will help you manage your condition.

Before you measure your blood pressure

For half an hour before a reading, you’ll need to avoid:

smoking or vaping
alcohol
exercise or physical activity
hot showers or baths
drinks with caffeine, including coffee, tea, or energy drinks.

Go to the toilet beforehand. A full bladder can affect your result.

Sit in an upright chair with your back fully supported.

Put the blood pressure monitor on a table or bench next to you.

Uncross your legs and put both feet flat on the floor.

Relax in this position for five minutes before taking your reading.

Image of man checking his blood pressure using a blood pressure monitor.

How to take an accurate blood pressure reading

To measure blood pressure accurately, use the same arm every time.
Place the blood pressure cuff around your bare upper arm, two fingers above your elbow.
The cuff should feel firm and the cable should face downwards.
Put your lower arm on the table with your palm up. The cuff should be at the same height as your heart.
Relax your hand. Don't clench your fist.
Sit still and don't talk while you measure your blood pressure.
Press the start button. The arm cuff will tighten and deflate automatically.
Record your first reading.
Wait one minute.
Take a second reading by repeating the steps above.

What do my blood pressure numbers mean?

Your blood pressure measurement is given in two numbers which are written one above the other, for example 120/80. This is said ‘120 over 80’.

The top number is the pressure in your blood vessels when your heart beats. This is systolic pressure.

The bottom number is when your heart relaxes. This is diastolic pressure.

An ideal blood pressure is 120/80, although this may vary depending on your individual circumstances.

Blood pressure chart

More about managing high blood pressure

Recording your blood pressure results

Record both readings in a diary or an online tool.

Download the Heart Foundation blood pressure logbook
Use an online blood pressure tool

Some home monitors will record and store your results.

How often should I check my blood pressure?

If your doctor has advised home monitoring, follow the instructions they’ve given you.

Otherwise, if you’ve just started home monitoring, take your blood pressure twice every day for two weeks – once in the morning and once in the evening.

Try to take it at around the same time every day.

Your morning blood pressure should be taken after sitting for five minutes, but before you've had breakfast or taken any medication.

Your evening blood pressure should be taken after dinner and any evening medication, and after five minutes in a sitting position. Take it before you lie down in bed.

When do I need to speak to my doctor or nurse?

If the doctor has suggested home monitoring, they will tell you when you need a follow up appointment.

Take your blood pressure results to your next appointment with your doctor or nurse.

They will give you a target blood pressure and advise how often you need to keep checking it. Not everyone's target blood pressure is the same.

If you have a reading that is 180/120 or higher, take a second reading five minutes later. If your blood pressure is still above 180/120, discuss your results with your GP or Healthline, preferably the same day or as soon as possible.

How accurate is a home blood pressure monitor?

Home blood pressure monitoring can be more accurate than the readings taken by your doctor or at your local pharmacy. That's because you're more relaxed at home.

If you aren’t sure about the accuracy of your blood pressure monitor, take it to a pharmacy and ask them to compare your monitor’s reading to their own device.

Tips for buying a blood pressure monitor

You may be wondering what to look for when buying a home blood pressure monitor. There are a few things to consider.

Where to buy a blood pressure monitor
Like most things these days, you’ll have the option of buying instore or online. It’s a good idea to try the model before making any decisions, even if you eventually purchase it online. This way you can:

test the cuff size
look at the instructions and consumer information
make sure you understand the features.

Look for a monitor with an upper arm cuff
Choose a monitor that has an upper arm cuff, not one that goes on the wrist. The reading will be more accurate if the cuff is at the same level as your heart.

Cuff size matters
You need a cuff that fits correctly. If it’s too big, or too small, you might get an inaccurate result.

The cuff should fit snugly around your upper arm, with just enough space to slide two fingertips underneath.

Clinically validated
Make sure your monitor is ‘clinically validated’. This means it has been checked and tested before it’s packaged to make sure it gives accurate results. You should be able to find this information on the packaging or in the instructions. You may also find information about the brand online.

If you’re unsure, you could ask your local pharmacist for more advice.

Display
Choose a monitor that has a clear, easy-to-read display. If you’re writing down your readings, make sure the result stays up long enough for you to record it.

Using an app
Some monitors sync with an app that tracks your results and lets you print them off if needed.

Alternatively, you can manually record results on a mobile tool or write them down in a logbook.

Understand the features
Home monitors offer a range of features depending on the brand. These may include:

risk category indicator – alerts you to high blood pressure readings
readings storage – records and stores your readings
irregular heart rate detection – detects abnormal heart rhythms such as atrial fibrillation
error indicator – tells you if you may have got a false reading due to movement
extended warranty.

Have a think about what you need and what you can afford.

What if I can’t afford a home monitor?

Some pharmacies, community health organisations, and charities offer free blood pressure checks.
Look online for further information or call your local pharmacy.

More about high blood pressure
Six ways to reduce your blood pressure

How to measure your BP at home

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